Which One of the Following Best Characterizes How Confidence Intervals

Which one of the following best characterizes how confidence intervals are used in reporting students' scores on standardized tests?

A) They indicate the norm group to which students are being compared.
B) They show the range of 10 percentile points within which each student's score falls.
C) They indicate how likely it is that each student has mastered a particular topic.
D) They show the range within which each student's actual ability level probably lies.